I am minting the NFT on Rinkeby Testnet through the smart contract I created. The minted NFT were shown on Opensea but not on Rarible. What could be the cause of this?
The NFTs minted from old contracts do show somehow.
Asked in Rarible's Discord server, it turns out Rarible was doing something with the testnet at that moment and the NFTs on testnet wasn't up-to-date until they finish doing that. There's nothing wrong on my smart contract.